@jmondi/browser-storage

An abstracted storage library for browser applications that interfaces with localStorage, sessionStorage, in-memory storage, or any custom serializer. It provides serialization capabilities with optional key prefixing for better storage management.

Installation

For Node.js:

pnpx jsr add @jmondi/browser-storage

For Deno:

deno add @jmondi/browser-storage

Usage

LocalStorage and SessionStorage are wrappers for window.localStorage and window.sessionStorage. You can add your own custom adapters to use Cookies or IndexedDB etc.

const storage = new LocalStorage({ prefix: "myapp__" });
const LOCAL_STORAGE = storage.defineGroup({ token: "jti", current_user: "u" });
// any primitive value
LOCAL_STORAGE.token.key; // "myapp__jti
LOCAL_STORAGE.token.set("newtoken");
LOCAL_STORAGE.token.get(); // "newtoken"
LOCAL_STORAGE.token.remove();

// any serializable object
LOCAL_STORAGE.current_user.key; // "myapp__u"
LOCAL_STORAGE.current_user.set({ email: "[email protected]" });
LOCAL_STORAGE.current_user.get(); // { email: "[email protected]" }
LOCAL_STORAGE.current_user.remove();

// pop removes and returns the value
LOCAL_STORAGE.current_user.set({ email: "[email protected]" });
LOCAL_STORAGE.current_user.pop(); // { email: "[email protected]" }
LOCAL_STORAGE.current_user.get(); // null

Use define for individual single storage keys, for example:

type UserInfo = { email: string };
const storage = new LocalStorage();
const USER_INFO_STORAGE = storage.define<UserInfo>("user_info");
USER_INFO_STORAGE.set({ email: "[email protected]" });
USER_INFO_STORAGE.get(); // gets the latest value
USER_INFO_STORAGE.remove(); // removes the value

You can also define keys dynamically

const storage = new LocalStorage();
storage.set("user2", { email: "[email protected]" });
console.log(storage.get("user2")); 

The LocalStorage class

Persists after closing browser

import { LocalStorage } from "@jmondi/browser-storage";

const storage = new LocalStorage();

The SessionStorage class

Resets on browser close

import { SessionStorage } from "@jmondi/browser-storage";

const storage = new SessionStorage();

Example Custom storage adapter

An example implementation of a custom adapter using js-cookie

import { type Adapter, BrowserStorage } from "@jmondi/browser-storage";
import Cookies from "js-cookie";

export class CookieAdapter implements Adapter {
  getItem(key: string): string | null {
    return Cookies.get(key) ?? null;
  }
  removeItem(key: string): void {
    Cookies.remove(key);
  }
  setItem(key: string, value: string, config?: Cookies.CookieAttributes): void {
    Cookies.set(key, value, config);
  }
}

const COOKIE_STORAGE = new BrowserStorage<Cookies.CookieAttributes>({
  prefix: "app_",
  adapter: new CookieAdapter(),
});
COOKIE_STORAGE.defineGroup({ cookie_thing: "my-cookie-thing-name" })
COOKIE_STORAGE.cookie_thing.key; // "app_my-cookie-thing-name"
COOKIE_STORAGE.cookie_thing.set("value");
COOKIE_STORAGE.cookie_thing.get(); // "value"

Configuration

Optional settings: prefix (key prefix), serializer (defaults to JSON).

import { BrowserStorage } from "./index.ts";

const storage = new LocalStorage({ prefix: 'app_', serializer: JSON });

Custom Serializers

To create a custom serializer, implement parse and stringify.

import superjson from "superjson";
import { StorageSerializer } from "@jmondi/browser-storage";

export class SuperJsonSerializer implements StorageSerializer {
  parse<T = unknown>(value: string): T { 
    return superjson.parse(value); 
  }
  stringify<T = unknown>(value: T): string { 
    return superjson.stringify(value); 
  }
}